Fire visibilityChange event on out-of-process iframes.

third_party/WebKit/Source/web/WebLocalFrameImpl.cpp

Index: third_party/WebKit/Source/web/WebLocalFrameImpl.cpp
diff --git a/third_party/WebKit/Source/web/WebLocalFrameImpl.cpp b/third_party/WebKit/Source/web/WebLocalFrameImpl.cpp
index 0893b67b0d59e7013896a1dce6d7647599e72786..000967d10b512a47036d14bfe7ede77622b4cbab 100644
--- a/third_party/WebKit/Source/web/WebLocalFrameImpl.cpp
+++ b/third_party/WebKit/Source/web/WebLocalFrameImpl.cpp
@@ -1795,7 +1795,7 @@ WebLocalFrameImpl* WebLocalFrameImpl::localRoot()
     // when the WebLocalFrame exists but the core LocalFrame does not.
     // TODO(alexmos, dcheng): Clean this up to only calculate this in one place.
     WebLocalFrameImpl* localRoot = this;
-    while (!localRoot->frameWidget())
+    while (localRoot->parent() && localRoot->parent()->isWebLocalFrame())
         localRoot = toWebLocalFrameImpl(localRoot->parent());
     return localRoot;
 }